Editor’s Note: Markus Pössel is a theoretical physicist turned astronomical outreach scientist. He is the managing scientist at the Centre for Astronomy Education and Outreach “Haus der Astronomie” in Heidelberg, Germany.
Your new post is loading...
NOTE: To subscribe to the RSS feed of Amazing Science, copy http://www.scoop.it/t/amazing-science/rss.xml into the URL field of your browser and click "subscribe".
This newsletter is aggregated from over 1450 news sources:
All my Tweets and Scoop.It! posts sorted and searchable:
You can search through all the articles semantically on my
NOTE: All articles in the amazing-science newsletter can also be sorted by topic. To do so, click the FIND buntton (symbolized by the FUNNEL on the top right of the screen) and display all the relevant postings SORTED by TOPICS.
You can also type your own query:
e.g., you are looking for articles involving "dna" as a keyword
MOST_READ • 3D_printing • aging • AI • anthropology • art • astronomy • bigdata • bioinformatics • biology • biotech • chemistry • computers • cosmology • education • environment • evolution • future • genetics • genomics • geosciences • green_energy • history • language • map • material_science • math • med • medicine • microscopy • nanotech • neuroscience • paleontology • photography • photonics • physics • postings • robotics • science • technology • video
Imagine an electronic implant that delivers a drug when triggered by a remote wireless signal — then harmlessly dissolves (no post-surgical infection concerns, no fuss, no muss) within minutes or weeks. That’s what researchers at Tufts University and the University of Illinois at Champaign-Urbana have demonstrated* in mice, using a resistor (as a source of heat for releasing drug and help dissolving the implant) and a power-receiving coil made of magnesium deposited onto a silk protein”pocket” that also protects the electronics and controls its dissolution time. There have been other implantable medical devices, but they typically use non-degradable materials that have limited operational lifetimes and must eventually be removed or replaced — requiring more surgery.
Devices were implanted in vivo in S. aureus-infected tissue and activated by a wireless transmitter for two sets of 10-minute heat treatments. Tissue collected from the mice 24 hours after treatment showed no sign of infection, and surrounding tissues were found to be normal. Devices completely dissolved after 15 days, and magnesium levels at the implant site and surrounding areas were comparable to levels typically found in the body. The researchers also conducted in vitro experiments in which similar remotely controlled devices released the antibiotic ampicillin to kill E. coli and S. aureus bacteria. The wireless activation of the devices was found to enhance antibiotic release without reducing antibiotic activity.
The research was published online in the Proceedings of the National Academy of Sciences Early Edition the week of November 24–28, 2014. and was supported by the National Institutes of Health and the National Science Foundation.
Mammoth cloning is closer to becoming a reality following the discovery of blood in the best-preserved specimen ever found.
An autopsy on a 40,000-year-old mammoth has yielded blood that could contain enough intact DNA to make cloning possible, galvanising scientists who have been working for years to bring back the extinct elephant relative. Tests are still being conducted on the blood to see if it will yield a complete genome – the genetic code necessary to build an organism.
The mammoth (nicknamed Buttercup) was discovered in 2013 on Maly Lyakhovsky Island in northern Siberia and excavated from the permafrost. The flesh was remarkably well-preserved, and oozed a dark red liquid when scientists cut into it. That liquid has now been confirmed as blood, following an autopsy conducted by scientists including Museum palaeobiologist Dr Tori Herridge.
'As a palaeontologist, you normally have to imagine the extinct animals you work on,' said Dr Herridge. 'So actually coming face-to-face with a mammoth in the flesh, and being up to my elbows in slippery, wet, and frankly rather smelly mammoth liver, counts as one of the most incredible experiences of my life.' The South Korean firm Sooam Biotech Research Foundation is leading the research project.
The noble gas xenon should be found in terrestrial and Martian atmospheres, but researchers have had a hard time finding it.
The prevailing theory claims that due to xenon’s weight -- it is a heavy gas -- it could be trapped in a planet’s core or in the mantle during the planet’s formation. Lawrence Livermore scientists and collaborators have discovered that the xenon can be trapped in the subsurface of the Earth, shedding new insights into the long-standing mysteries of the “missing xenon” in earth science.
The discovery of the noble gas xenon (Xe) has led to the synthesis of hundreds of Xe compounds (for example, it is thought that a compound made up of xenon and iron may lie in Earth’s core). Its reactivity also has been estimated to be the cause of its depletion by a factor of 20 relative to the lighter noble gases -- neon, argon and krypton -- in the atmosphere of Earth, Mars and other planetary bodies. Specifically, xenon reacts with hydrogen and ice at high pressures to form stable compounds.
The team used a high pressure diamond anvil cell, which applies extreme pressures on materials, and advanced synchrotron X-ray scattering techniques to show that under high pressure and temperature, a silicate mineral, made up mostly of silver, irreversibly inserts xenon into its micropores and undergoes charge separation. As opposed to other noble gases such as argon and krypton, xenon stays within the pores even after pressure and heat are decreased.
“This is a new chemical reaction that could account for the ‘missing xenon’ observed in terrestrial and Martian atmospheres," said Hyunchae Cynn, one of the LLNL physicists involved in the research. The team found missing xenon from the atmosphere trapped within porous rocks in a planet’s core or mantle.
Google is approaching hospitals and universities with a new pitch. Have genomes? Store them with us. The search giant’s first product for the DNA age is Google Genomics, a cloud computing service that it launched last March but went mostly unnoticed amid a barrage of high profile R&D announcements from Google, like one late last month about a far-fetched plan to battle cancer with nanoparticles (see “Can Google Use Nanoparticles to Search for Cancer?”).
Google Genomics could prove more significant than any of these moonshots. Connecting and comparing genomes by the thousands, and soon by the millions, is what’s going to propel medical discoveries for the next decade. The question of who will store the data is already a point of growing competition between Amazon, Google, IBM, and Microsoft.
Google began work on Google Genomics 18 months ago, meeting with scientists and building an interface, or API, that lets them move DNA data into its server farms and do experiments there using the same database technology that indexes the Web and tracks billions of Internet users.
“We saw biologists moving from studying one genome at a time to studying millions,” says David Glazer, the software engineer who led the effort and was previously head of platform engineering for Google+, the social network. “The opportunity is how to apply breakthroughs in data technology to help with this transition.”
Some scientists scoff that genome data remains too complex for Google to help with. But others see a big shift coming. When Atul Butte, a bioinformatics expert at Stanford heard Google present its plans this year, he remarked that he now understood “how travel agents felt when they saw Expedia.”
The explosion of data is happening as labs adopt new, even faster equipment for decoding DNA. For instance, the Broad Institute in Cambridge, Massachusetts, said that during the month of October it decoded the equivalent of one human genome every 32 minutes. That translated to about 200 terabytes of raw data.
This flow of data is smaller than what is routinely handled by large Internet companies (over two months, Broad will produce the equivalent of what gets uploaded to YouTube in one day) but it exceeds anything biologists have dealt with. That’s now prompting a wide effort to store and access data at central locations, often commercial ones. The National Cancer Institute said last month that it would pay $19 million to move copies of the 2.6 petabyte Cancer Genome Atlas into the cloud. Copies of the data, from several thousand cancer patients, will reside both at Google Genomics and in Amazon’s data centers.
The idea is to create “cancer genome clouds” where scientists can share information and quickly run virtual experiments as easily as a Web search, says Sheila Reynolds, a research scientist at the Institute for Systems Biology in Seattle. “Not everyone has the ability to download a petabyte of data, or has the computing power to work on it,” she says.
Innovation from MIT could allow many biological components to be connected to produce predictable effects.
Researchers have made great progress in recent years in the design and creation of biological circuits — systems that, like electronic circuits, can take a number of different inputs and deliver a particular kind of output. But while individual components of such biological circuits can have precise and predictable responses, those outcomes become less predictable as more such elements are combined.
A team of researchers at MIT has now come up with a way of greatly reducing that unpredictability, introducing a device that could ultimately allow such circuits to behave nearly as predictably as their electronic counterparts. The findings are published this week in the journal Nature Biotechnology, in a paper by associate professor of mechanical engineering Domitilla Del Vecchio and professor of biological engineering Ron Weiss.
The lead author of the paper is Deepak Mishra, an MIT graduate student in biological engineering. Other authors include recent master’s students Phillip Rivera in mechanical engineering and Allen Lin in electrical engineering and computer science. There are many potential uses for such synthetic biological circuits, Del Vecchio and Weiss explain. “One specific one we’re working on is biosensing — cells that can detect specific molecules in the environment and produce a specific output in response,” Del Vecchio says. One example: cells that could detect markers that indicate the presence of cancer cells, and then trigger the release of molecules targeted to kill those cells.
It is important for such circuits to be able to discriminate accurately between cancerous and noncancerous cells, so they don’t unleash their killing power in the wrong places, Weiss says. To do that, robust information-processing circuits created from biological elements within a cell become “highly critical,” Weiss says.
A sculpture so tiny that it cannot be seen by the naked eye is claimed to be the smallest sculpture of the human form ever created. Measuring a picayune 20 x 80 x 100 microns, artist Jonty Hurwitz’s tiny human statue is part of a new series of equally diminutive new sculptures that are at a scale so infinitesimally miniscule that each of the figures is approximately equal in size to the amount your fingernails grow in around about 6 hours, and can only be viewed using a scanning electron microscope.
Sculpted with an advanced new nano 3D printing technology coupled with a technique called multiphoton lithography, these works of art are created using a laser that uses the phenomenon of two photon absorption. In this way, an object is traced out by a laser in a block of light-sensitive monomer or polymer gel, and the excess is then washed away to leave a solid form.
As this method of two photon absorption only takes place at the tiny focal point of the laser, it essentially creates a tiny 3D pixel (a voxel) at that juncture. The laser is then moved along a fractional distance under computer control and the next voxel in the series is formed. In a long and painstaking process that takes place over many hours, the complete 3D sculpture is assembled voxel by voxel.
"We live in an era where the impossible has finally come to pass," said Hurwitz. "In our own little way we have become demi-gods of creation. Contemporary art, in my humble view, needs to reflect the human condition as it is today, it needs to represent the state of society at the time of its creation. Take a moment to consider that only 6,000 years ago we were painting crude animal images on the walls of caves with rocks. We have come far. This nano sculpture is the collective achievement of all of humanity. It is the culmination of thousands of years of R&D."
Emerging evidence indicates that there are factors within the blood of young animals that have the ability to restore youthful characteristics to a number of organ systems in older animals. Recent work regarding age-related cardiac hypertrophy identified growth/differentiation factor 11 (GDF11) as one such factor with rejuvenating powers. As animals become older, levels of circulating GDF11 normally decline.
Remarkably, injecting GDF11 into aged mice recapitulates the effects of heterochronic parabiosis, reversing cardiac hypertrophy7. However, it remained unclear whether the effects of GDF11 were unique to the heart.
Sinha et al.8 have now shown that increasing the systemic levels of GDF11 in aged mice also has rejuvenating effects on skeletal muscle. Aged mice injected daily with recombinant GDF11 (rGDF11) for four weeks have greater numbers of satellite cells, the local muscle stem cell population. Moreover, these satellite cells have less DNA damage and generate more myogenic cells in culture. rGDF11 supplementation also improves the in vivo regenerative capacity of satellite cells, resulting in the growth of larger muscle fibers after injury. Treatment with rGDF11 even increases exercise endurance and grip strength, demonstrating that the improvements seen in satellite cells relate to a functional enhancement in muscle performance. While it remains unclear whether these results are due primarily to effects on skeletal muscle, particularly given the known enhancement of cardiac function observed with rGDF11 treatment, this work demonstrates that a single systemic factor can help restore physiological properties of youth.
Studies regarding the rejuvenating capacity of young blood and rGDF11 have also been extended to the aged brain by Katsimpardi et al.9. The authors focused on the adult neural stem cells (NSCs) of the subventricular zone (SVZ) and found that heterochronic parabiosis enhances proliferation of Sox2+ NSCs in the aged mice. SVZ NSCs differentiate into neuroblasts that migrate to the olfactory bulb, and heterochronic parabiosis almost doubles the number of new neurons in the olfactory bulb of aged mice. Interestingly, these mice exhibit improved olfactory discrimination, but whether this behavioral change results directly from the enhanced neurogenesis or more generally to the whole-animal effects of heterochronic parabiosis is not yet known.
Stellar explosions called gamma ray bursts emit beams of radiation that could render 90% of galaxies barren of complex life. The universe may be a lonelier place than previously thought. Of the estimated 100 billion galaxies in the observable universe, only one in 10 can support complex life like that on Earth, a pair of astrophysicists argues. Everywhere else, stellar explosions known as gamma ray bursts would regularly wipe out any life forms more elaborate than microbes. The detonations also kept the universe lifeless for billions of years after the big bang, the researchers say.
"It's kind of surprising that we can have life only in 10% of galaxies and only after 5 billion years," says Brian Thomas, a physicist at Washburn University in Topeka who was not involved in the work. But "my overall impression is that they are probably right" within the uncertainties in a key parameter in the analysis.
Scientists have long mused over whether a gamma ray burst could harm Earth. The bursts were discovered in 1967 by satellites designed to spot nuclear weapons tests and now turn up at a rate of about one a day. They come in two types. Short gamma ray bursts last less than a second or two; they most likely occur when two neutron stars or black holes spiral into each other. Long gamma ray bursts last for tens of seconds and occur when massive stars burn out, collapse, and explode. They are rarer than the short ones but release roughly 100 times as much energy. A long burst can outshine the rest of the universe in gamma rays, which are highly energetic photons.
That seconds-long flash of radiation itself wouldn't blast away life on a nearby planet. Rather, if the explosion were close enough, the gamma rays would set off a chain of chemical reactions that would destroy the ozone layer in a planet's atmosphere. With that protective gas gone, deadly ultraviolet radiation from a planet’s sun would rain down for months or years—long enough to cause a mass die-off.
How likely is that to happen? Tsvi Piran, a theoretical astrophysicist at the Hebrew University of Jerusalem, and Raul Jimenez, a theoretical astrophysicist at the University of Barcelona in Spain, explore that apocalyptic scenario in a paper in press at Physical Review Letters.
One of the most mysterious forms of life may turn out to be a rich and untapped source of antibacterial drugs. The mysterious life form is Archaea, a family of single-celled organisms that thrive in environments like boiling hydrothermal pools and smoking deep sea vents which are too extreme for most other species to survive.
“It is the first discovery of a functional antibacterial gene in Archaea,” said Seth Bordenstein, the associate professor of biological sciences at Vanderbilt University who directed the study, “You can’t overstate the significance of the antibiotic resistance problem that humanity is facing. This discovery should help energize the pursuit for new antibiotics in this underexplored group of life.”
Until the late 1970s, biologists thought that Archaea were just weird bacteria, but then a landmark analysis of their DNA showed that they represent an independent branch on the tree of life that stretches back more than three billion years. The realization that Archaea could be a source of novel pharmaceuticals emerges from a study of widespread horizontal gene transfer between different species conducted by a team of scientists from Vanderbilt University and Portland State University in Oregon.
Our brains start soaking in details from the languages around us from the moment we can hear them. One of the first things infants learn of their native languages is the system of consonants and vowels, as well as other speech sound characteristics, like pitch. In the first year of life, a baby’s ear tunes in to the particular set of sounds being spoken in its environment, and the brain starts developing the ability to tell subtle differences among them—a foundation that will make a difference in meaning down the line, allowing the child to learn words and grammar.
But what happens if that child gets shifted into a different culture after laying the foundations of its first native language? Does it forget everything about that first language, or are there some remnants that remain buried in the brain?
According to a recent PNAS paper, the effects of very early language learning are permanently etched into the brain, even if input from that language stops and it’s replaced by another language. To identify this lasting influence, the researchers used functional magnetic resonance imaging (fMRI) scans on children who had been adopted to see what neural patterns could be identified years after adoption.
Because not all linguistic features have easily identifiable effects on the brain, the researchers decided to focus on lexical tone. This is a feature found in some languages that allows a single arrangement of consonants and vowels to have different meanings that are distinguished by a change in pitch. For example, in Mandarin Chinese, the word “ma” with a rising tone means “hemp”—the same syllable with a falling tone means “scold.”
People who speak tone languages have differences in brain activity in a certain region of the brain’s left hemisphere. This region activates in response to pitch differences that are used to convey a difference in linguistic meaning; non-linguistic pitch is processed in the right hemisphere. Tone information is learned very early in life: infants learning Chinese languages (including Mandarin and Cantonese) show signs of recognizing tonal contrasts as early as four months.
CrAssphage is a bacteriophage (also known as phages or bacterial viruses), a member of a group of viruses that infect bacteria.
Prof Edwards and his colleagues named this virus after the Cross-Assembly (CrAss) software program used to discover it.
Interestingly, CrAssphage was discovered entirely by accident.
While sifting through data from previous studies on gut-inhabiting viruses, the virologists noticed an unusual cluster of viral DNA – about 97,000 base pairs long.
When they checked this discovery against a comprehensive listing of known viruses, they came up empty. They then screened for CrAssphage across the database of the NIH’s Human Microbiome Project, and Argonne National Laboratory’s MG-RAST database, and again found it in abundance in samples.
To prove that CrAssphage they discovered in their data actually exists in nature, the researchers used DNA amplification technique to locate the virus in the original samples used to build NIH’s database.
“So we have a biological proof that the virus they found with the computer actually exists in the samples. This was a new virus that about half the sampled people had in their bodies that nobody knew about,” said Dr John Mokili of San Diego State University, who is a co-author of the paper describing the discovery in the journal Nature Communications.
The fact that CrAssphage is so widespread indicates that it probably isn’t a particularly young virus, either. “As far as we can tell, it’s as old as humans are. We’ve basically found it in every population we’ve looked at,” Prof Edwards said. According to the scientists, CrAssphage infects one of the most common types of gut bacteria, Bacteroidetes.
Wildlife photographer Jeff Cremer has discovered what appears to be a new type of bioluminescent larvae. He told members of the press recently that he was walking near a camp in the Peruvian rainforest at night a few years ago, when he came upon a side of exposed earth upon which there were many little green glowing dots. Taking a closer look, he found that each dot was in fact the glowing head of a worm of some sort. He posted pictures of what he'd found on Reddit which were eventually spotted by entomologist Aaron Pomerantz, with the Tambopata Research Center. After contacting Cremer, Pomerantz made a pilgrimage to see the worms, gathered some samples and set to work studying them. Shortly thereafter, he determined that the worms were the larvae of an unknown type of beetle, likely a type of click beetle.
Entomologists still don't know what kind of beetle the larvae would grow into, but are determined to find out—they aren't even sure if they are from known species. There are a lot of different kinds of click beetles, approximately 10,000 species, about 200 of which are known to be bioluminescent. The entomologists believe the larvae get their luminescence from a molecule called Luciferin, which is also found in the compound used by fireflies to light up the night sky.
How is it that vultures can live on a diet of carrion that would at least lead to severe food-poisoning, and more likely kill most other animals? This is the key question behind a recent collaboration between a team of international researchers from Denmark’s Centre for GeoGenetics and Biological Institute at the University of Copenhagen, Aarhus University, the Technical University of Denmark, Copenhagen Zoo and the Smithsonian Institution in the USA. An “acidic” answer to this question is now published in the scientific journal Nature Communications.
When vultures eat lunch they happily strip the rotting carcasses they find back to the bone. And if, however, the animal’s hide is too tough to easily pierce with their beak, they don’t hesitate to enter it using other routes, among them the back entrance – so to speak: via the anus. Although their diet of meat that is both rotting and liberally contaminated with feces would likely kill most other animals, they are apparently immune to the cocktail of deadly microbes within their dinner such as Clostridia, Fuso- and Anthrax-bacteria.
To investigate vultures’ ability to survive eating this putrid cocktail, a group of scientists generated DNA profiles from the community of bacteria living on the face and gut of 50 vultures from the USA. On average, the facial skin of vultures contained DNA from 528 different types of micro-organisms, whereas DNA from only 76 types of micro-organisms were found in the gut.
Michael Roggenbuck explains: "Our results show there has been strong adaptation in vultures when it comes to dealing with the toxic bacteria they digest. On one hand vultures have developed an extremely tough digestive system, which simply acts to destroy the majority of the dangerous bacteria they ingest. On the other hand, vultures also appear to have developed a tolerance towards some of the deadly bacteria – species that would kill other animals actively seem to flourish in the vulture lower intestine."
A leg growing out of your mouth. Extra legs pushing out of your side. Walking parts where your swimming bits should be. If you’re a tiny crustacean in Nipam Patel’s lab, chances are good you’re not quite right—and that’s just the way these UC Berkley geneticists like it. By inducing birth defects in arthropods called parhyale, Patel’s team makes “monsters” that deliver a one-two punch, offering insights into the mechanics of evolution, and into ways we could treat (or even prevent) human birth defects and disease in the future.
The questions that drive Patel’s lab are deceptively simple, and brain-crushingly profound: How did Earth’s organisms become different from one another? How is an embryo “programmed” to know what it should look like? How might changes to that programming have advanced evolution itself? This frustrated, flailing parhyale—which, thanks to Patel’s crew, was born with almost perfect walking appendages where its swimming appendages should be—is helping to revolutionize how we think about all of it.
Welcome to the world of Hox genes, a roughly 600-million-year-old “toolkit” that controls how body plans—the head-to-tail layout of our symmetrical, physical selves—develop. Once thought to exist only in flies, Hox genes rocked biology in the mid-’80s when it was discovered that they were in every single animal on Earth. And while the number of Hox genes tends to vary according to how complex you are (insects have 8; humans have 39), the genes themselves have changed so little in millions of years that they’re what’s called "highly conserved" across species.
In labs, that means flies function surprisingly well when one of their Hox genes is swapped for the corresponding chicken Hox gene. From an evolutionary perspective, it means earthworms, humpback whales, butterflies, and humans are all just variations on a theme. “Despite the fact that we don’t think of ourselves as looking anything like a fly,” says Patel, “our development basically uses the same genes.”
Hox genes are “master instructors”—each oversees development in a different region of the body (head, thorax, abdomen), turning other genes on and off to ensure you grow the right form for your species. “In the field in general,” says Patel, “I think we’ve increasingly convinced people that single genes can have big roles in evolution,” but his team hunts proof, examples of how small tweaks to the Hox toolkit may have given rise to Earth’s massive species diversity.
In a paper published in PNAS on Monday November 24, scientists laid out a robust new framework based on in situ observations that will allow scientists to describe and understand how phytoplankton assimilate limited concentrations of phosphorus, a key nutrient, in the ocean in ways that better reflect what is actually occurring in the marine environment. This is an important advance because nutrient uptake is a central property of ocean biogeochemistry, and in many regions controls carbon dioxide fixation, which ultimately can play a role in mitigating climate change.
"Until now, our understanding of how phytoplankton assimilate nutrients in an extremely nutrient-limited environment was based on lab cultures that poorly represented what happens in natural populations," explained Michael Lomas of Bigelow Laboratory for Ocean Sciences, who co-led the study with Adam Martiny of University of California - Irvine, and Simon Levin and Juan Bonachela of Princeton University. "Now we can quantify how phytoplankton are taking up nutrients in the real world, which provides much more meaningful data that will ultimately improve our understanding of their role in global ocean function and climate regulation."
To address the knowledge gap about the globally-relevant ecosystem process of nutrient uptake, researchers worked to identify how different levels of microbial biodiversity influenced in situ phosphorus uptake in the Western Subtropical North Atlantic Ocean. Specifically, they focused on how different phytoplankton taxa assimilated phosphorus in the same region, and how phosphorus uptake by those individual taxa varied across regions with different phosphorus concentrations. They found that phytoplankton were much more efficient at assimilating vanishingly low phosphorus concentrations than would have been predicted from culture research. Moreover, individual phytoplankton continually optimized their ability to assimilate phosphorus as environmental phosphorus concentrations increased. This finding runs counter to the commonly held, and widely used, view that their ability to assimilate phosphorus saturates as concentrations increase.
"Prior climate models didn't take into account how natural phytoplankton populations vary in their ability to take up key nutrients, "said Martiny. "We were able to fill in this gap through fieldwork and advanced analytical techniques. The outcome is the first comprehensive in situ quantification of nutrient uptake capabilities among dominant phytoplankton groups in the North Atlantic Ocean that takes into account microbial biodiversity."
Mark Hart, a scientist and engineer in Lawrence Livermore National Laboratory’s (LLNL) Defense Technologies Division, has been awarded the 2015 Surety Transformation Initiative (STI) Award from the National Nuclear Security Administration’s (NNSA) Enhanced Surety Program.
The STI award aims to stimulate and encourage the development of potentially transformational nuclear weapon surety technologies and explore innovative, preferably monumental shift solutions, to unmet surety needs.
“STI’s task is to reach beyond the traditional stockpile stewardship function of maintaining existing nuclear weapon capability in the absence of supercritical testing,” said Robert Sherman, enhanced surety federal program manager in NNSA’s Technology Maturation Division. “STI is intended not to maintain or polish ‘your grandfather’s Oldsmobile,’ but to go beyond it: to invent devices and technologies that serve the 21st century nuclear security needs of the American people better than they are served by existing Cold War legacy technologies.”
Hart’s winning proposal is for Intrinsic Use Control (IUC), a concept that is capable of providing improved quantifiable safety and use control within a nuclear weapon. Nuclear weapons exist, therefore control is essential. Use control of a weapon is focused on providing unencumbered authorized use while restricting unauthorized use. Safety, use control and physical security work in concert for the weapon’s surety. IUC provides a less than 10-18 chance of controlling or operating an individual protected component, and a less than 10-72 chance of controlling or operating the entire protected system.
Researchers at the RIKEN Quantitative Biology Center in Japan, together with collaborators from the University of Tokyo, have developed a method that combines tissue decolorization and light-sheet fluorescent microscopy to take extremely detailed images of the interior of individual organs and even entire organisms. The work, published in Cell, opens new possibilities for understanding the way life works—the ultimate dream of systems biology—by allowing scientists to make tissues and whole organisms transparent and then image them at extremely precise, single-cell resolution.
To achieve this feat, the researchers, led by Hiroki Ueda, began with a method called CUBIC (Clear, Unobstructed Brain Imaging Cocktails and Computational Analysis), which they had previously used to image whole brains. Though brain tissue is lipid-rich, and thus susceptible to many clearance methods, other parts of the body contain many molecular subunits known as chromophores, which absorb light. One chromophore, heme, which forms part of hemoglobin, is present in most tissues of the body and blocks light. The group decided to focus on this issue and discovered, in a surprise finding, that the aminoalcohols included in the CUBIC reagent could elute the heme from the hemoglobin and by doing so make other organs dramatically more transparent.
Using the method, they took images of mouse brains, hearts, lungs, kidneys, and livers, and then went on to attempt the method on infant and adult mice, and found that in all cases they could get clear tissues. They used the technique of light-sheet fluorescent microscopy, which involves taking "slices" of tissues without having to actually cut into it, to gain 3D images of the organs. To test the practicability of the method, they examined the pancreases of diabetic and non-diabetic mice, and found clear differences in the isles of Langerhans, the structures in the pancreas that produce insulin.
Although these methods could not be used in living organisms, since they require the tissues to be fixed using reagents, they could, according to Kazuki Tainaka, the first author of the paper, be very useful for gaining new understanding of the 3D structure of organs and how certain genes are expressed in various tissues. He said, "We were very surprised that the entire body of infant and adult mice could be made nearly transparent by a direct transcardial CUBIC perfusion coupled with a two-week clearing protocol. It allowed us to see cellular networks inside tissues, which is one of the fundamental challenges in biology and medicine."
For the last two years, the US$2.25 million Nokia Sensing X Challenge has lured entrants from around the globe to submit groundbreaking technologies that improve access to health care. A panel of experts have awarded this year's grand prize to Massachusetts-based DNA Medical Institute (DMI), whose hand-held device is capable of diagnosing ailments in minutes, using only a single drop of blood.
The DMI team were selected from 11 finalists. Among them were Swiss team Biovotion, whose wearable computer monitors vital signs such heart rate and breathing, along with the US-based Eigen Lifescience team, whose low-cost, portable device is capable of testing for Hepatitis B in less than 10 minutes. But it was DMI's Reusable Handheld Electrolyte and Lab Technology for Humans system (rHealth) that impressed the judges most.
"Our expert judging panel reviewed a very exciting group of sensing technologies, all with the potential to address a wide array of diagnostic and personal health needs,” said Dr. Peter H. Diamandis, chairman and CEO of X Prize, the foundation behind the competition. “DMI’s rHealth system embodies the original goal of the Nokia Sensing X Challenge, to advance sensor technology in a way that will enable faster diagnoses and easier, more sophisticated personal health monitoring.”
The rHealth diagnostic system requires the patient to provide just a single drop of blood, with this small sample mixed with nanoscale test strips and streamed past lasers to process its signature. This can then identify ailments ranging from simple colds, to the flu, to more serious diseases like Ebola, with claimed gold standard accuracy. It comes accompanied by a wearable patch which is worn to monitor vital signs, such as breathing and heart rate, sharing data over Bluetooth with either the device or the user's smartphone.
In addition to the portable device, DMI produced two other diagnostics instruments under the rHealth label, intended more for researchers in the lab and medical professionals. It developed the tools in collaboration with NASA and with space travel in mind, which it says pushed them to focus on simplicity and accuracy for their design.
When a medication enters the bloodstream, it ends up being concentrated in the liver – after all, one of the organ's main functions is to cleanse the blood. This means that if a drug is going to have an adverse effect on any part of the body, chances are it will be the liver. It would seem to follow, therefore, that if a pharmaceutical company wanted to test the safety of its products, it would be nice to have some miniature human livers on which to experiment – which is just what San Diego-based biotech firm Organovo is about to start selling.
Known as exVive3D, the three-dimensional liver models measure just a few millimeters across, and are created using a 3D bioprinter. The device incorporates two print heads, one of which deposits a support matrix, and the other of which precisely places human liver cells in it.
The resulting models are composed of living human liver tissue, and incorporate hepatocytes, stellate, and endothelial cells – just like a real, full-sized liver. They also produce liver proteins such as albumin, fibrinogen and transferrin, plus they synthesize cholesterol.
Additionally, the cells are arranged in a 3D orientation relative to one another, as they would be naturally. By contrast, the liver cell cultures currently used to test pharmaceuticals are two-dimensional, and thus may not always function in the same manner as the actual organ.
THERE'S A ROW of books on a shelf in Marc ten Bosch's living room that contains a crash course in higher dimensions. Titles like Flatland. Einstein, Picasso: Space, Time and the Beauty That Causes Havoc. The Fourth Dimension and Non-Euclidean Geometry in Modern Art. A young-adult novel called The Boy Who Reversed Himself. They're all devoted to helping our brains break out of the three dimensions in which we exist, to aid our understanding of a universe that extends beyond our perception.
This is not just a hypothetical pursuit. Most of us think of time as the fourth dimension, but modern physics theorizes that there is a fourth spatial dimension as well—not width, height, or length but something else that we can't experience through our physical senses. From this fourth dimension, we would be able to see every angle of the three-dimensional world at once, much as we three-dimensional beings can take in the entirety of a two-dimensional plane. Mathematician Bernhard Riemann came up with the concept in the 19th century, and physicists, artists, and philosophers have struggled with it ever since. Writers from Wilde to Proust, Dostoevsky to Conrad invoked the fourth dimension in their work. H. G. Wells' Invisible Man disappeared by discovering a way to travel along it. Cubism was in part an attempt by Picasso and others to visualize what fourth-dimensional creatures might see.
Still, most of us are no closer to fundamentally comprehending the fourth dimension than we were when Riemann first conceived it. People have written papers, drawn diagrams, taken psychedelics, but what we really want to do is witness it. Mathematician Rudy Rucker wrote that he had spent 15 years trying to imagine 4-D space and been granted for his labors “perhaps 15 minutes' worth of direct vision” of it.
But for the past five years, ten Bosch has been trying to take us directly into it, in the form of a videogame called Miegakure. The game, essentially a series of puzzles, augments the usual arsenal of in-game movement by allowing the player's avatar, with the press of a button, to travel along the fourth spatial dimension. Building something so ambitious has consumed ten Bosch's life. Chris Hecker, a friend and fellow game designer, marvels that ten Bosch “can't even see the game he's making.” Ten Bosch, who is 30, describes his daily schedule as “wake up, work on the game, go get lunch somewhere, work on the game, go to sleep.” Even after toiling for half a decade, he is still only about 75 percent done.
But among the tight-knit community of indie game developers, Miegakure is a hotly anticipated title. The select few who have played it have showered it with praise. 1 Ten Bosch has twice been invited to preview it at the prestigious Experimental Gameplay Workshop at the annual Game Developers Conference in San Francisco. He won the “amazing game” award at IndieCade, the biggest annual showcase of independent games.
The interactions in Miegakure are basic: You can move the character, you can make him jump, you can press a button to enter one of the Torii gates (most of which lead to a puzzle). And you can press another button to travel along the unseeable fourth dimension. When you press it, the world appears to morph and fold in on itself, revealing colored slices to walk on. These slices look like parallel worlds; they're even visually distinct so that players can distinguish them as separate realms. One looks like desert, another like grass, another like ice. Walking onto each slice and then pressing the button seems to transport you into each new universe.
But here's the thing: They're not new universes. They're 3-D cross-sections—“hyperslices,” maybe?—of a 4-D shape. The “morph” button, which appears to make the world around you swirl and the objects within it disappear, does not in fact move your character even a millimeter. You're not teleporting. You're just changing perspective—except you're not looking left or right, not up or down or forward or back. You're looking into the unseeable fourth dimension and only then traveling along it.
Over time, the game nudges you toward an understanding of this by including 3-D objects that move in more than one “universe” when your character pushes them. You find maps that help to illustrate how the spaces intersect. And soon you're performing the miracles that mathematicians say a 4-D being could perform in three-dimensional space: walking through walls, making blocks seem to float in the air, disappearing and reappearing, and interlocking two seemingly impenetrable rings. The math is solid—every shape in the game is defined by four coordinates instead of three—but just as when an illusionist performs that same ring trick, it feels like magic.
Qubits based on trapped ions can be prepared and manipulated with record-breaking accuracy, offering a promising scalable platform for quantum computing.
The realization, two decades ago, that quantum mechanics can be a powerful resource to speed up important computational tasks  led to intense research efforts to find adequate physical systems for quantum computation. One of the hurdles to a viable technology is the requirement to prepare, manipulate, and measure quantum bits (qubits) with near perfect accuracy: Imperfect control leads to errors that can accumulate over the computation process. Techniques like quantum error correction and fault-tolerant designs can, in principle, overcome these errors. But these strategies can be successful only if the error probabilities are lower than a threshold value. They also increase the complexity of the required quantum hardware, since they require additional qubits. Recent calculations  suggest that an error probability of less than 1% would enable fault-tolerant codes, and that lower error probabilities dramatically decrease the number of qubits required for such codes.
The quality of qubit manipulation in a number of physical systems has dramatically improved in the past few years [3, 4], raising hopes that a quantum computer, at a large enough scale to carry out meaningful computations, might be within reach. Now, Thomas Harty at the University of Oxford, UK, and colleagues  are reporting an important contribution to this goal with the demonstration that qubits consisting of trapped 43Ca+ions can be manipulated with record high fidelities (in quantum information theory, fidelity is a measure of the “closeness” of two quantum states). Their experiments suggest trapped-ion schemes could potentially provide the basic fundamental building blocks of a universal quantum computer.
Behavior can be affected by events in previous generations which have been passed on through a form of genetic memory, animal studies suggest. Experiments showed that a traumatic event could affect the DNA in sperm and alter the brains and behaviour of subsequent generations.
A Nature Neuroscience study shows mice trained to avoid a smell passed their aversion on to their "grandchildren". Experts said the results were important for phobia and anxiety research. The animals were trained to fear a smell similar to cherry blossom. The team at the Emory University School of Medicine, in the US, then looked at what was happening inside the sperm.
They showed a section of DNA responsible for sensitivity to the cherry blossom scent was made more active in the mice's sperm. Both the mice's offspring, and their offspring, were "extremely sensitive" to cherry blossom and would avoid the scent, despite never having experienced it in their lives. Changes in brain structure were also found.
"The experiences of a parent, even before conceiving, markedly influence both structure and function in the nervous system of subsequent generations," the report concluded. The findings provide evidence of "trans-generational epigenetic inheritance" - that the environment can affect an individual's genetics, which can in turn be passed on.
Prof Marcus Pembrey, from University College London, said the findings were "highly relevant to phobias, anxiety and post-traumatic stress disorders" and provided "compelling evidence" that a form of memory could be passed between generations. He commented: "It is high time public health researchers took human trans-generational responses seriously. "I suspect we will not understand the rise in neuropsychiatric disorders or obesity, diabetes and metabolic disruptions generally without taking a multigenerational approach."
The most detailed aerodynamic simulation of hummingbird flight conducted to date demonstrates that it achieves its aerobatic abilities through a unique set of aerodynamic forces.
The sight of a tiny hummingbird hovering in front of a flower and then darting to another with lightning speed amazes and delights. But it also leaves watchers with a persistent question: How do they do it?
Now, the most detailed, three-dimensional aerodynamic simulation of hummingbird flight conducted to date has definitively demonstrated that the hummingbird achieves its nimble aerobatic abilities through a unique set of aerodynamic forces that are more closely aligned to those found in flying insects than to other birds.
The new supercomputer simulation was produced by a pair of mechanical engineers at Vanderbilt University who teamed up with a biologist at the University of North Carolina at Chapel Hill. It is described in the article “Three-dimensional flow and lift characteristics of a hovering ruby-throated hummingbird” published this fall in the Journal of the Royal Society Interface.
For some time researchers have been aware of the similarities between hummingbird and insect flight, but some experts have supported an alternate model which proposed that hummingbird’s wings have aerodynamic properties similar to helicopter blades. However, the new realistic simulation demonstrates that the tiny birds make use of unsteady airflow mechanisms, generating invisible vortices of air that produce the lift they need to hover and flit from flower to flower.
You might think that if the hummingbird simply beats its wings fast enough and hard enough it can push enough air downward to keep its small body afloat. But, according to the simulation, lift production is much trickier than that. For example, as the bird pulls its wings forward and down, tiny vortices form over the leading and trailing edges and then merge into a single large vortex, forming a low-pressure area that provides lift. In addition, the tiny birds further enhance the amount of lift they produce by pitching up their wings (rotate them along the long axis) as they flap.
Hummingbirds perform another neat aerodynamic trick – one that sets them apart from their larger feathered relatives. They not only generate positive lift on the downstroke, but they also generate lift on the upstroke by inverting their wings. As the leading edge begins moving backwards, the wing beneath it rotates around so the top of the wing becomes the bottom and bottom becomes the top. This allows the wing to form a leading edge vortex as it moves backward generating positive lift.
Frogs, as we all know, lay eggs which eventually grow to become tadpoles. And tadpoles, because they have no legs, need water to survive. But the brilliant-thighed poison frog doesn't live in water, instead, it lives among leaf litter on the floor of the Amazonian rainforest. To keep their tadpoles alive, the adults carry them from puddle to puddle on their backs. Thus, the frogs need to know the location of all the puddles in their little part of world. Somehow, it seems, they build mental maps that allow them to move from one water nursery to the next without deviating.
To better understand the frogs, the researchers fitted several of them with tiny transmitters that allowed for tracking every move the volunteer frogs made. Then, they placed the frogs in different parts of the forest to see how well they did in finding their way back to where they lived. Remarkably, the researchers found that if the frogs were placed within a certain familiar range they were able to march straight back to their home without having to even pause or look around. Frogs that were placed in unfamiliar terrain on the other hand, became lost for awhile and had to work to get home. The researchers found that the range for familiar territory ranged at least up to 100 meters from where the frogs called home, though prior research has shown that such frogs typically roam in a circular area roughly 600 meters in diameter.
The microbes that live in your body outnumber your cells 10 to one. Recent studies suggest these tiny organisms help us digest food and maintain our immune system. Now, researchers have discovered yet another way microbes keep us healthy: They are needed for closing the blood-brain barrier, a molecular fence that shuts out pathogens and molecules that could harm the brain.
The findings suggest that a woman's diet or exposure to antibiotics during pregnancy may influence the development of this barrier. The work could also lead to a better understanding of multiple sclerosis, in which a leaky blood-brain barrier may set the stage for a decline in brain function.
The first evidence that bacteria may help fortify the body’s biological barriers came in 2001. Researchers discovered that microbes in the gut activate genes that code for gap junction proteins, which are critical to building the gut wall. Without these proteins, gut pathogens can enter the bloodstream and cause disease.
In the new study, intestinal biologist Sven Pettersson and his postdoc Viorica Braniste of the Karolinska Institute in Stockholm decided to look at the blood-brain barrier, which also has gap junction proteins. They tested how leaky the blood-brain barrier was in developing and adult mice. Some of the rodents were brought up in a sterile environment and thus were germ-free, with no detectable microbes in their bodies. Braniste then injected antibodies—which are too big to get through the blood-brain barrier—into embryos developing within either germ-free moms or moms with the typical microbes, or microbiota.
The studies showed that the blood-brain barrier typically forms a tight seal a little more than 17 days into development. Antibodies infiltrated the brains of all the embryos younger than 17 days, but they continued to enter the brains of embryos of germ-free mothers well beyond day 17, the team reports online today in Science Translational Medicine. Embryos from germ-free mothers also had fewer intact gap junction proteins, and gap junction protein genes in their brains were less active, which may explain the persistent leakiness.